.cell {
  border: 1px solid black;
  width: 100px;
  height: 100px;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 80px;
}
.row {
  display: flex;
}
.gameOver{
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,.5);
  font-size: 100px;
  color: white;
  display: flex;
  justify-content: center;
  align-items: center;
}